IIRC, a View renders to one or more Canvas3D - and fills them. So my first guess is to have in fact 2 Canvas3D, maybe even tied together and maintained by Swing. Not sure wether it can be done with SimpleUniverse, but at least it can be done without it. :-/

you may got me wrong, 1. IMHO the problem with two canvas3D for splitscreen is that I want to switch to single player modus at runtime so I need switching to 1 double-sized onscreen canvas and awt/swing component attchjing/detaching isn't very fast..

2. I don't assume the blitting itself to be slow. I thought about the offscreen rendering: I may be wrong, but is offscreen rendering fully hardware accelerated ?

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